Patent · US Expired

Semiconductor device lead frame with etched through holes

US4862246A · kind A · utility

236Cited by
13References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 24, 1988
Grant dateAug 29, 1989
Priority date
Expiry dateFeb 24, 2008

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/12569
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

Those portions (i.e., the inner lead portions) of the leads of a semiconductor device, which are sealed by a package, are formed with a plurality of depression in at least the surfaces and backs thereof such that the depressions have a smaller diameter at their bottoms than at their surfaces. As a result, both the adhesion strength between a sealer as the package and the inner lead portions of the leads and the mechanical strength of the leads are improved even in a semiconductor device having numerous leads. Moreover, the inner lead portions can be formed in their sides with a number of notches, which can be combined with those depressions to better improve the adhesion strength between the sealant and the inner lead portions of the leads and the mechanical strength of the leads.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.